Reach About The Impacts Of No.11 Coal Seam Exploitation On Upper No.3 Coal Mine In The Mine Of Sangshuping

Sangshuping coal mine is coal and gas outburst mine, minable seam is No. 2, No.3 and No.11 coal seam. The No.3 coal seam is the primary mineable coal seam which has the characteristics of thickness, "three soft" and high gas content.So it has great pressure on gas disaster prevention and control during mining. The government of measures gas regional was mining on the upper liberation layer in the past, meaning taking the No.2 coal seam as liberation layer with the unsatisfying effect on practical applications. In view of the No.11 coal seam on the bottom of the No.3, we consider that put the No.11 coal seam as the under-liberation layer of the No.3 coal seam. The layer spacing of no.3 and no.11 coal seam is 57~ 63 m, the average is 60.7 m. The 3105 working face which arrange in no.11 coal seam thickness is 1.8 ~ 3.5 m, the average is 2.65 m. Using all caving method treat gob.In order to understand the effect on no.11 after coal mining the no. 3 coal seam, mainly includes the situation of separation near the floor strata. Distribution of the “three zones” after the 3105 working face in mining, strata movement stability time after the mining. This paper adopts the method of field measurement and theoretical analysis, mainly through the monitoring system of the 3314 gas drainage lane which is between No. 3 and No.11 coal seam monitors the movement rule of overlying rock strata during the period of mining the 3105 working face. Through the analysis of data, combining relevant theories we draw that Caving zone for 10 m to 16 m, fissure zone for 47 m to 52 m, rock caving angle for 74°,the minimum layer spacing between No.3 and No.11 coal seam is 57 m.So the no.3 coal locate at the curve subsidence zone. The maximum subsidence of no. 3 coal’s floor is 1950 mm, the maximum data of separation in the layer which near the floor strata is less than 30 mm. Analyses the strata movement in different periods and the boundary effect on strata movement. By the results of monitoring we know that the stability time of upper strata of gob is about two months. There has a lot of benefits on deployment for No.3 and No.11 coal mining according to the movement of overburden rock stable time is short. In the end, using the ratio method of decision and discriminance of wall rocks balance analyze the feasibility of ascending mining. Comprehensive the above research results, the integrity and continuity of no. 3 coal is good. Ascending mining is feasible. It can provides the basis of mining design for other similar working face in Sangshuping coal mine. It can also be used as a basis for similar geological conditions in assign working face.